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Questions tagged [shift]

Questions related to the usage of the right and/or left shift key on the keyboard. For questions regarding bitwise shift operations use [bit-shift]

Questions related to the usage of the right and/or left Shift key on the keyboard. For questions regarding bitwise shift operations use

1054 questions
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Move column by name to front of table in pandas

Here is my df: Net Upper Lower Mid Zsore Answer option More than once a day 0% 0.22% -0.12% 2 65 Once a day 0% 0.32% -0.19% …
Boosted_d16
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Java, Shifting Elements in an Array

I have an array of objects in Java, and I am trying to pull one element to the top and shift the rest down by one. Assume I have an array of size 10, and I am trying to pull the fifth element. The fifth element goes into position 0 and all elements…
darksky
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Comparing previous row values in Pandas DataFrame

import pandas as pd data={'col1':[1,3,3,1,2,3,2,2]} df=pd.DataFrame(data,columns=['col1']) print df col1 0 1 1 3 2 3 3 1 4 2 5 3 …
jth359
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Disable New Line in Textarea when Pressed ENTER

I am calling a function whenever someone press enter in the textarea. Now I want to disable new line or break when enter is pressed. So new line should work when shift+enter is pressed. In that case, the function should not be called. Here is…
Hassan Sardar
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c get nth byte of integer

I know you can get the first byte by using int x = number & ((1<<8)-1); or int x = number & 0xFF; But I don't know how to get the nth byte of an integer. For example, 1234 is 00000000 00000000 00000100 11010010 as 32bit integer How can I get all…
Kamran224
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IntelliJ Shift Shift Shortcut in Visual Studio (Global Search)

After doing some Java I fell in love with some of IntelliJ's features. Especially the keyboard shortcut SHIFT +SHIFT which lets you jump to any other file. This is a huge time savesaver. Now that I'm back in VS I really miss that feature when I'm…
AlexVPerl
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Can anybody please explain (my $self = shift) in Perl

I'm having a really hard time understanding the intersection of OO Perl and my $self = shift; The documentation on these individual elements is great, but none of them that I've found touch on how they work together. I've been using Moose to make…
Alex H Hadik
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Is 'shift' evil for processing Perl subroutine parameters?

I'm frequently using shift to unpack function parameters: sub my_sub { my $self = shift; my $params = shift; .... } However, many on my colleagues are preaching that shift is actually evil. Could you explain why I should prefer sub…
Nikolai Prokoschenko
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Rotate array elements to the left (move first element to last and re-index)

Is it possible to easily 'rotate' an array in PHP? Like this: 1, 2, 3, 4 -> 2, 3 ,4 ,1 Is there some kind of built-in PHP function for this?
Dylan
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How do I shift an array of items up by 4 places in Javascript

How do I shift an array of items up by 4 places in Javascript? I have the following string array: var array1 = ["t0","t1","t2","t3","t4","t5"]; I need a function convert "array1" to result in: // Note how "t0" moves to the fourth position for…
Darryl Hebbes
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Is left-shifting a signed integer undefined behavior in C++03?

According to C++03, 5.8/2, left-shifting is defined as follows: The value of E1 << E2 is E1 (interpreted as a bit pattern) left-shifted E2 bit positions; vacated bits are zero-filled. If E1 has an unsigned type, the value of the result is E1…
sharptooth
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Shuffle a List in Scala

I have question to for shuffle list in scala using scala.util.Random. For example I have val a = cyan val b = magenta val c = yellow val d = key val color = Random.shuffle.List(a,b,c,d).toString //but it doesn't work ;( so I want the val color to…
Deden Bangkit
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Optimization levels in gcc changing c program behaviour

I'm seeing behaviour I don't expect when compiling this code with different optimization levels in gcc. The function test should fill a 64 bit unsigned integer with ones, shift them shift_size bits to the left, and return the 32 low bits as a 32 bit…
user1142769
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data.table | faster row-wise recursive update within group

I have to do the following recursive row-by-row operation to obtain z: myfun = function (xb, a, b) { z = NULL for (t in 1:length(xb)) { if (t >= 2) { a[t] = b[t-1] + xb[t] } z[t] = rnorm(1, mean = a[t]) b[t] = a[t] +…
jayc
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how to do circular shift in numpy

I have a numpy array, for example a = np.arange(10) how can I move the first n elements to the end of the array? I found this roll function but it seems like it only does the opposite, which shifts the last n elements to the beginning.
LWZ
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